Ten of the world elite are competing at Moscow's Tal Memorial, which ends today and is one of the strongest tournaments in chess history. But the winner in the event's first half was a flu virus which affected several grandmasters and encouraged a minimalist, cautious approach. Ukraine's Vasily Ivanchuk wore a face mask, and a high 80 per cent of the first five round games were drawn.

The sickest player was Magnus Carlsen, 19, who had trained beforehand with Garry Kasparov and was expected to unleash some opening bombs in his campaign to become world No 1. But Norway's golden teen was close to defeat against Vlad Kramnik in the opening round and then opted to fight his bug by antibiotics and a solid, low risk strategy.

As the bug subsided, the leaders before the final round were Vlad Kramnik 5.5/8, Vasily Ivanchuk and the world champion, Vishy Anand, 5, Magnus Carlsen 4.5. Below, Anand gives a lesson in how to cash in a small edge.

Svidler began with the Grunfeld 3...d5, the most popular opening in Moscow. White chose a calm line, Black's 13...Nb4 improved on theory, and three moves later Rfd8-d6 would have been level. Svidler's more passive plan provoked an attack along the f file, but Black was still holding until 25...fxe4? (f4!) after which 29 b4! cracked the defences. If 29...Rc8 30 bxc5 Qxc5 31 Rexd4 wins a piece, and in the game Anand also gained decisive material.